Ok, I know this may seem like a strange question, but I'm going to be in Manhattan for two or three days, and there's so much damn stuff to do there that I can't figure it out. From those of you who have spent some time there, how do you recommend two poor college students to fill some time?
Much appreciated.

Take the PATH from the WTC site over to New Jersey (first stop) then have a nice walk along the Hudson, the Manhattan skyline is beautiful from there, you need some distance to really feel how mighty those buildings are. Great for photo ops. too

The great thing about New York is that you probably know all the places you want to go already. Central Park, Chinatown (Have Dim Sum and the Golden Unicorn on East Broadway, it's great!), go to the top of the Empire State building. Do NOT miss the Metropolitan Museum of Art. If you are into good food, go ahead and start making reservations. (For Italian, any of Mario Batali's restaurants are steller..my personal favorite is Babbo though. Nobu is the best Japanese in the city, and you are guaranteed to see celebrities there.) For lesser treats, make sure to try an H&H bagel on the upper west side. (While you are there, head on over to the cathedral of St. John the Divine, which is incomplete, but when completed will be the largest cathedral in the world). Might as well stop by Columbia University while you are there...It's a quiet spot if you find the need to escape the city for a few minutes. Grant's Tomb is also nearby to the Cathedral and Columbia (On Riverside Drive). It's quite an impressive monument. I second that you need to see Grand Central, it's really something else. There are so so many others...if you have any questions shoot me an e-mail, I go to school here in Manhattan and would be happy to help you with anything!

If its a good waether I would suggest you to visit the Central park. That park is really amazing.
And the USS Intrepid Museum is really great too. I have been there 3 times my self. So that museaum is really worth a visit. I know that's not really inside Manhattan but it doesn't take long to walk there at all.

Of course Times Square is cool for people who have never been, I suggest not coming during business hours, as you will invariably be yet another body on the sidewalk and make me have to elbow you out of the way kidding, but the lights do look cooler at night.

If you wake up early enough you can see Good Morning America being taped in times sq. http://www.abc.com

Of course, take a walk around lower manhattan, checking out the ground zero area, and walking along Wall St, seeing the oldest Church in American (I think) at Wall St and Broadway. The stock exchange down there too, and either hit Battery Pary or the South Street Seaport for a nice walk along the water. Across the Brooklyn Bridge in Brooklyn is the Promenade from which you have a most splendid view of lower Manhattan.

SoHo and TriBeCa are two neighborhoods that are cool to walk around. SoHo moreso, and yes, the walk along W Broadway (DIFFERENT from Broadway) is great because it is quintessential SoHo, though Broadway is cool too, just more crowded. You can also find cheap eats around SoHo.

For going out on the cheap, and eating on the cheap, I'd suggest the East Village for college kids. Its fun, its dark, its moody, its college types and fun. This is everything east of Broadway from Houston St up to 14th St.

Take the 2 hour cruise around Manhatten Island. I did this last time I went and it was a very relaxing couple of hours and you get some great views of the Skyline and they take you out past Liberty island too.

There is a free bus to the boats, it runs from outseide the Empire state building, just stand at any bus stop and stick your arm out and they will stop for you, but the name of the company escapes me !!.

If you cannot afford that, then take the Staten Island ferry, it's free and goes right past Liberty so you can get some ok pics, but it goes a bit further out than the tourist boats so you need a good camera for close up shots.

Also go pay a visit to G-BOAD, the Concorde that is at the Intrepid.

If you go up the Empire State, try and go just before sunset then you get to see the city in daylight, at sunset and in the dark all for one price !!.

The Statue of Liberty is very overrated, it is beautiful but I expected it to be bigger. Your best bets (and some of the cheapest) are the MET, Central Park, SOHO. Harlem is pretty cool too, (it is more than you expect). Try to avoid Rockefeller Center it is swarming with tourists all day and is packed in morning (Today show), the only good place there is Radio City that is a beautiful theatre (take the tour). Also, if you want to see a play go to the TKS stand in the middle on Times square after lunch it has some good shows for pretty cheap (just be flexible).